Re: fees on membership plans
It used to be a massive problem in the UK, back in the day with things like wine, magazine or music (tape/CD etc) "clubs".
It's classic dark patterns - make it as difficult to cancel as possible - you have a limited window, have to write in to a specific address using specific words, have to send back what was previously sent to you but would cost an arm and a leg. etc etc.
I don't know if gyms are still guilty of it, but they used to use tactics such as having to visit a specific gym on a specific day and time to speak to the only person who could approve the cancellation that you had to also bring in writing. Not their problem if said person wasn't there when you tried etc.
For online subscriptions where there is nothing tangible exchanging hands, this sort of thing should be illegal.
My own other pet hate is booking sites that charge a "booking fee" despite it being done online and no physical tickets changing hands. Also should be utterly illegal.